Big Berkey Water Filters

Berkey's most recent laboratory testing indicates that the Black Berkey Purification Elements will initially reduce Fluoride up to 99.9%. Typically, carbon-based elements that reduce Fluoride begin to lose that ability rather quickly. This may be the case with Black Berkey Elements as their efficiency at removing Fluoride likely plays out long before the 3,000-gallon life of the element.

There are a number of filters on the market that utilize carbonized bone char (a media that Berkey purposely chooses not to use), and that make claims for Fluoride reduction, without informing their customers that the fluoride removing ability of the filters plays out quickly. The reason this occurs is because it takes a very large amount of media to remove small amounts of Fluoride. Therefore, there is not enough media in such filters to remove Fluoride effectively over the long term. For example, we have testing for a competitor’s 3-filter system that utilizes bone char for their Fluoride removal claims and, as one would expect, those elements become quickly exhausted. Testing shows that their efficiency declines from 100% removal to 81.4% removal after filtering a mere 45 gallons. This is equivalent to only 15 gallons per element required for them to experience a dramatic ~20% decline in efficiency.

This same effect likely occurs with Black Berkey Elements after a few hundred gallons. For that reason Berkey developed a more durable and longer lasting solution for Fluoride reduction by creating the replaceable Berkey PF-2 Fluoride reduction elements. The media in a set of Berkey PF-2 elements can reliably remove Fluoride contaminants for up to 1,000 gallons, which is less than the 3,000 gallon life of the Black Berkey Elements but again, that is why they were designed to be replaceable. This enables the users to reliably remove Fluoride contaminants from their water while taking full advantage of the 3,000 gallon life of their Black Berkey Elements.

The Black Berkey Purification Element’s job is to remove a wide variety of potential contaminants, while the Berkey PF-2 Post Filter’s job is to remove Fluoride contaminants that the Black Berkey Purification Elements may begin to miss after extended use. Actual capacity is dependent on the presence of other competing contaminants in the source water. High levels of arsenic and heavy metals may reduce the capacity and efficiency of these elements.

Hydraulic fracturing, or fracking, has resulted in a boom in the oil and gas industry across the US. But the rapid growth of the industry has raised the issue of how to dispose of the billions of gallons of wastewater generated as a result of fracking operations.

A recent study has found that treating this wastewater before releasing it into the environment does not necessarily make it safe. The study, which was recently published in the American Chemistry Society's journal Environmental Science & Technology, has reported that release of treated fracking wastewater has led to a Pennsylvanian watershed becoming contaminated with radioactive material and hormone disrupting chemicals, both of which pose a human health risk.

According to the US Energy Information Administration, in 2015, more than 50% of all oil produced in the US, and 66% of gas produced was a result of the hydraulic fracturing method used to extract oil and gas from deep below the Earth's surface. This method of extraction is expected to expand even further in the future. Yet while fracking has led to a transition away from burning coal, which could effectively reduce atmospheric emissions, large volumes of wastewater are produced as a result, which contain a wide array of pollutants, including heavy metals, salts, hormone disrupting chemicals, polycyclic aromatic hydrocarbons and radioactive material, which could potentially pose both an environmental and human health risk.

A Pennsylvanian report estimated 1.7 billion gallons of wastewater was produced by 10,000 oil and gas wells at fracking sites in the Marcellus Shale in 2015. This wastewater is collected by wastewater treatment facilities that, after providing limited treatment, release the partially treated water into nearby surface waters. William Burgos together with a team of scientists from Penn State University, Colarado State University and Dartmouth College wanted to determine whether treating and releasing fracking wastewater in this manner might be having an impact on the environment.

In order to assess this, they analyzed porewater and sediment samples they had collected from a lake situated further downstream from two fracking wastewater treatment facilities in Pennsylvania. They found high levels of salts, alkaline earth metals, organic chemicals and radium all tended to occur within the same layer of the sediments collected. The organic chemical contaminants included both hormone disrupting nonylphenol ethoxylates and carcinogenic polycyclic aromatic hydrocarbons. Sediment layers that were deposited between 5-10 years ago — during a time when fracking wastewater disposal peaked — had the highest concentrations of contaminants. High concentrations of radium were found in samples collected 12 miles further downstream of the wastewater treatment plants. The authors conclude that while it is not yet clear what, if any, potential environmental and health risks this contamination may pose, they suggest that it would be prudent to impose more stringent regulations on fracking wastewater disposal in order to protect both environmental and human health.

Philadelphia Congressman, Brendan Boyle, on Thursday reintroduced a bill that will set a national drinking water standard for the now widespread perfluorinated compounds — a common drinking water contaminant that poses a grave public health risk, The Intelligencer has reported.

Perfluorinated compounds include hundreds of chemicals, but PFOA and PFOS are the two of the best known as they have recently been detected in drinking water sources serving 15 million people across the United States.

The Safe Drinking Water Act's Unregulated Contaminant Monitoring Rule (UCMR) currently requires the US Environmental Protection Agency (EPA) to test drinking water across the country for up to 30 unregulated drinking water contaminants and no more, every five years.

The PFCs, PFOS and PFOA, were included on the list of unregulated contaminants to be tested for in the third UCMR testing program conducted by the EPA, which resulted in their being discovered in many drinking water supplies between 2013-2015. As there is currently no drinking water standard set for these contaminants, the EPA has set a drinking water "health advisory limit" of 70ppt for these contaminants. But according to Boyle, this limit isn't enough.

"Every day we continue to learn more about the scope and seriousness of perfluorinated compounds across the country. It's past time we address these contaminants with the seriousness they merit," Boyle said.

Although brief, the bill introduced by Boyle, H.R. 3106, stipulates that the EPA introduce a drinking water standard for chemicals in the perfluorinated compound family, including PFOS and PFOA within two 2 years of the bill being passed.

The bill, which is co-sponsored by congressmen Patrick Meehan of Upper Darby and Brian Fitzpatrick of Middletown, and by D-N.Y. Rep. Paul Tonko and D-N.J. Rep. Frank Pallone, forms part of a broader spectrum of bills put forward by Pallone in an effort to update and redefine the Safe Drinking Water Act to in fact make drinking water safer for consumers to drink.

"All Americans deserve to have confidence in the safety of their drinking water, no matter what state they live in or what activities have taken place in their communities," Boyle added.

Yet even though this is well overdue, it's highly unlikely that the bills will go unchallenged. Both Pallone and Boyle introduced similar bills in 2016, which ultimately were not passed. And while Boyle's current bill has gained some support from both within and outside his party, Pallone's bill H.R. 1068, is currently not as well supported.

While politicians do their thing behind the scene, people across the country are still being exposed to unsafe levels of PFCs in their drinking water. But consumers can be proactive and take measures to remove contaminants such as these from their water by investing in a good quality drinking water filter, such as a filter from the Berkey range, that is capable of removing PFCs from the water they drink.

Food and water are an essential requirement for health and well being, but for young children, both are a source of exposure to lead, which can lower a child's IQ and lead to behavioral problems. If we want to protect our children's health and ensure they are able to learn and develop mentally, we need to be more proactive when it comes to reducing their exposure to lead both in the environment and in the food and drinks they consume.

A recent report released by the Environmental Defense Fund (EDF) has revealed that many foods, particularly baby foods, contain lead and are thus an important source of exposure to this harmful contaminant.

For the study, the EDF analyzed eleven years of data collected by the Food and Drug Administration (FDA) between 2003-2013. They found lead in 20% of baby foods they sampled, and 14% of other non-baby food products sampled. Of the baby foods that contained lead, eight types had detectable levels of lead in over 40% of the food samples tested. More samples of baby foods consisting largely of grape and apple juice and carrots had detectable levels of lead than regular non-baby food versions of these products. The EDF found that over 1 million children ingest more lead than the limit set by the FDA. The report suggests that the societal benefits of eliminating lead exposure in food completely would amount to over $27 billion per year.

It is essential that both the FDA and food producers implement measures to reduce lead exposure through food, particularly baby food. The EDF has outlined the following recommendations to the FDA, manufacturing companies and parents, to reduce levels of lead exposure through food:

Recommendations to the FDA:

• Ensure that all materials that foods come into contact with during preparation are lead-free if there is any chance that lead in those materials can contaminate the food;
• Acknowledge the inadequacy of current international standards set for fruit juice;
• Update the safety limits for lead as well as food safety guidelines to reflect recent scientific knowledge of the public health risks associated with lead to improve safety of children; and
• Encourage food manufacturing companies to take measures to reduce levels of lead in food, and implement enforcement action when safely limits are breached.

Recommendations to food manufacturers:

• Set a lead target of less than one part per billion of lead for lead in baby foods and other food products consumed primarily by young children;
• Strive to minimize lead contamination by sourcing lead-free ingredients. (Note: As water forms a large component of fruit juices and other food products, manufacturers should also ensure that water used in the manufacture process is not contaminated with lead);
• Undertake frequent testing during the manufacturing process to identify all sources of lead contamination so that appropriate corrective action can be taken; and
• Make a public commitment to reduce lead levels in food products by setting limits that are safe for public health and maintaining these limits through proactive product stewardship.

Recommendations to parents:

The EDF encourages parents to consult with their family pediatrician to become more aware of sources of lead exposure so that they can take measures to actively reduce their child's exposure to lead. Parents should also contact representatives of their favorite food brands to check whether the manufacturer regularly monitors lead levels in its products and, particularly in the case of baby food/juice products, that lead levels are under 1 ppb.

Parents should also have their drinking water tested for lead, as this is yet another common source of lead exposure. If lead levels are high, drinking water should be filtered with a good quality water filter to ensure that the water your children drink does not pose a health risk.
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Freshwater is our most precious resource, yet surface waters and groundwater are both vulnerable to contamination from various sources. The severity of the health impact on humans varies according to the pollutants involved, with some contaminants only having a relatively mild health impact, while others can pose a more severe health hazard.

While consumers who receive their drinking water from a municipal water supply will have their water tested for them, people who get their drinking water from a private well will need to take their own measures to ensure their drinking water is safe, as it is their responsibility alone.
Consequently, private well owners should be aware of common water contamination issues and their symptoms to enable them to quickly detect and respond to any sign of well pollution before they pose any risk to human health. But, how can you tell if your drinking water is contaminated — what common symptoms should alert you that your water may be contaminated?

There are typically three clues that indicate your drinking water may be contaminated — if any one of these symptoms are present, there is a chance that your water may be suspect.

1. Cloudy or Discolored Water

When water is cloudy, murky or discolored, there could potentially be foreign particles such as silt or rust present. While many foreign particles are usually harmless themselves, their presence may indicate a failure within the water treatment or water supply system that could mean there are other more harmful contaminants, such as disease causing bacteria, present. Similarly, water that comes out the tap cloudy and then clears a few minutes after being poured may indicate a fault in the water filtration system. If water stains toilet bowls, baths, sinks or laundry, your water may be contaminated — green tinged stains are a good indicator that water is highly acidic, while brown or rust stains are a good indicator that your drinking water has high concentrations of dissolved iron present.

2. Strange Tasting Water

If your drinking water tastes brackish or salty it's likely that sodium levels will be high, while water that has a distinctive chemical taste is most likely polluted with chemical contaminants. Extremely alkaline or acidic water will also taste strange, with highly alkaline water typically tasting soapy, while highly acidic water and water with high levels of dissolved iron tend to leave a metallic aftertaste in the mouth.

2. Foul Smelling Water

If your water smells bad, it is a good indicator that something is amiss. One common symptom of water contamination is water that smells of rotten eggs. This foul odor is either caused by bacteria present in the water or by dissolved hydrogen sulfide. If the foul odor is only given off by hot water, it may be coming from your hot-water cylinder. Water that has a strong smell of chlorine has likely been treated with large amounts of chlorine at the water treatment plant. Water that smells dank and musty indicates there is most likely rotting vegetation held in suspension. If you drinking water is foamy and smells like washing detergent it may have been polluted by seepage from a cracked septic tank. Water that smells like fuel or oil has most likely been contaminated with petroleum products that have leaked out of a damaged fuel tank.

The above symptoms are physical indications that your drinking water may be contaminated, however, many other contaminants that pose a health risk to humans are not so easily detected unless you have the water tested. A good quality drinking water filter will be able to remove many of the contaminants that cause the symptoms above, plus many other drinking water contaminants that are not readily detectable by sight, taste or smell.

A recent study conducted by the Environmental Working Group (EWG) and scientists from the Social Science Environmental Health Research Institute at Northeastern University in Boston has revealed the presence of highly fluorinated chemical toxins, known as PFASs or PFCs, in drinking water serving 15 million people across 27 states, as well as from over 48 military and industrial sources across the country.

The two research teams collaborated to develop an interactive map from a combination of drinking water data obtained from the Environmental Protection Agency (EPA) and readily available data on PFC contamination from industry, fire-fighting training sites, civilian airports and military air-force bases.

"This is a one stop shop to track how pervasive the PFC contamination problem is in the U.S.," said Bill Walker, co-author of the report and managing editor of EWG. "For the first time we're reporting the full results of the EPA water testing, as well as known industrial spills and sites with military contamination, to provide a complete picture of where these PFCs are detected."

The source of contamination was identified at forty-seven of the polluted sites, with twenty-one of these cases stemming from military bases, twenty from industrial plants and seven from civilian fire-fighting operations. Some sites had more than one source of contamination.

After receiving a National Science Foundation grant to study the social impact of PFASs in 2014, the Social Science Environmental Health Research Institute set about investigating the impact on water quality and public health, analyzing data collected by concerned civil and military communities, who had begun testing for these toxic chemical compounds.

However, it is still very worrying that in many cases the source of these pollutants has not yet been identified, and at this stage it is also unclear how widespread the contamination may be. Currently, the EPA only tests drinking water for unregulated chemicals if the water supply serves over 10,000 consumers, and only tests for 30 chemicals over a three-year period. In communities such as Hoosick Falls, in the state of New York, where drinking water testing was commissioned by residents, PFCs have been found in drinking water. It is critical that the source of these toxic chemical pollutants that continue to contaminate drinking water is identified.

"Americans should be outraged," said David Andrews, a senior scientist at EWG. "As we uncover the pervasive pollution of drinking water, the chemical companies have already shifted production to a similar set of chemicals that are likely no better. Federal agencies have known for decades that this entire family of chemicals is toxic and they haven't passed drinking water regulations. These chemicals do not break down in the environment and the amount of PFCs in your blood could be 100 times higher than the level of the chemical detected in your drinking water."

Knowledge of the extent of PFC contamination within communities is expanding and is proving to be widespread. This raises a huge health concern, as exposure to PFCs is associated with cancer, weakened immunity function, thyroid disease and other health issues.

Walker finds it remarkable that America, considered the wealthiest country in the world, cannot guarantee its citizens that the water flowing from their taps is 100% safe to drink and that it will have no long-term health risks.

Over the last twenty-five years, the EPA hasn't added a single new drinking water pollutant to the Safe Drinking Water Act. This is due in part to the EPA being under-resourced, and in part due to pressure by the chemical industry who fights any new regulations. The only way limits will be set for these toxic chemicals in the near future is if they are implemented at state level.

In an earlier study, the EWG reported that even at very low concentrations, PFOA — the chemical used in Teflon non-stick coatings — can harm animal fetuses, and posed a grave public health risk. Yet, the average levels found in each state are at least five times higher than levels considered to be safe, and in some cases as much as 175 times higher.

Earlier this year, DuPont and its subsidiary company Chemours were forced to pay $671 million in lawsuit settlements to around 3,500 Ohio and West Virginia residents after their drinking water become contaminated by a carcinogenic chemical used in Teflon. Yet, while these plaintiffs have been awarded a settlement and this case is now closed, PFOA contamination is still widespread throughout the world.

This new interactive map, which will continue to be updated as information on other areas that are contaminated becomes known, serves as the most comprehensive tool available for tracking PFC contamination in the United States.

A Study of Public Perceptions of Water Infrustructure

A new study conducted by researchers from Indiana University indicates that the average American does not fully understand how clean drinking water is supplied to their home, nor what happens to wastewater that is flushed away. This is concerning considering that this knowledge and information is crucial to addressing some of the water related challenges we are currently facing, including prolonged drought, and water contamination due to failing water infrastructure.

For the study, which was recently published in the scientific journal Judgment and Decision Making, 500 university students were asked to sketch diagrams depicting how water is delivered to the taps in their home and how it makes its way back into the natural environment. Only 71% of the participants drew a water treatment plant (29% did not include water treatment as part of their water supply system), while only 36% included a wastewater treatment plant into their water system (64% failed to include a wastewater treatment facility in their plan).

Lead author, Shahzeen Attari of IU's School of Public and Environmental Affairs (SPEA) warns that climate change is likely to increase both the competition for water as well as the risks associated with the water supply. "Water infrastructure is increasingly fragile," said Attari. "It's going to take political will and public support to respond to new and old risks, and we may not support the adaptation strategies we need if we take our water systems for granted. Whether it's in schools or through other means, public environmental education must address these gaps."

Attari together with Kelsey Hinton and Kelsey Poinsatte-Jones, two former graduate students of the SPEA, conducted the research in two phases. For the first phase of the project, they asked water experts to provide a sketch of a domestic water supply system.

The students were then asked the following question:

"Please draw a diagram illustrating your understanding of the processes by which clean water reaches the tap in the average home in the United States. Please draw how water reaches the home from its original source(s) and is then returned to the natural environment. Show all the processes that the water goes through."

Only 7% of the students had a good understanding of how a water system worked, while many students drew an idealized "magic" version of a water system (below).

The student's lack of awareness doesn't mean that they don't care. Over a third of them indicated that they considered water quantity on a weekly- or sometimes even daily basis. Their primary concerns are water cleanliness, limited water supply or failures in the water infrastructure system that result in water contamination.

Of all our resources, drinking water is the most essential of all, Poinsatte-Jones points out. Most people take access to safe drinking water for granted, however the complex behind-the-scenes water network infrastructure which makes this possible is obscure and therefore very often not fully understood.

Considering all the water related risks we are currently facing, it is vitally important that we are able to make informed decisions regarding our water supplies, management and policies, stressed Hinton, who indicates that their study suggests we are currently not in a position to do that.

All living things require water for their survival. Humans are no exception. We all require a supply of clean, unpolluted drinking water, as it is essential for our health and well being. However, drinking water very often contains a myriad of contaminants, many of which can pose serious health risks to human health, therefore proper water treatment is essential to remove pollutants.

Cryptosporidium and Giardia, both of which the berkey water filters filter out from the water, are two parasites commonly found in drinking water that can cause disease. Cryptosporidium and Giardia have developed life strategies that enable them to survive long intervals in the environment between hosts. When they exit the host they enter a dormant phase, where they are protected by a tough exterior shell. During this dormant phase of their life cycle they a known as microbial cysts. Microbial cysts are resistant to chemical treatment processes, and often mechanical filtering is required to remove them from drinking water. When microbial cysts are ingested, the gastric juices in the intestine break down the hard exterior coating, releasing the parasites, which quickly become active and rapidly multiply.

How infection can take place

Infection with Cryptosporidium and Giardia can occur through exposure to infected animals, or to contact with the feces of infected animals. Very often the cysts are carried into waterways by runoff, where a person can become infected by ingesting contaminated drinking water, or by ingesting water that contains the cysts while swimming or boating.

Cryptosporidium and Giardia infection are common in the developed world, but are even more prevalent in third world countries, where water treatment infrastructure and water quality measures are lacking.

Life Cycle of Cryptosporidium and Giardia

After the Cryptosporidium or Giardia cysts are swallowed, they enter the digestive tract, where digestive juices break down the exterior shell, releasing the parasites. Before being excreted from the body, the parasites once again form a protective outer shell to aid their survival outside the host. Once they are excreted from the host they can be transmitted to another victim by person-to-person contact or through unhygienic or unsanitary conditions, where the cycle is repeated in the next host.

Cryptosporidium under the microscope.

Symptoms of Disease from Microbial Cysts

Ingestion of Cryptosporidium or Giardia cysts, and consequent infection by these parasites, causes the diseases cryptosporidiosis and giardiasis respectively. Symptoms of these diseases include diarrhea, abdominal pain, nausea, vomiting, dehydration, weight loss, and fever. These symptoms usually last for a week or two, but can last for as long as a month, and often recur. People suffering from immune deficiencies, including AIDS, cancer, and transplant patients that are being treated with medication that may compromise the immune system, are most at risk of infection. Giardiasis may also effect the rate of growth and development in children, and can cause malnutrition.

Preventing Infection

• In order prevent infection from these water borne parasites, the following precautionary measures are advised:
• Practice good hygiene: wash hands before eating or preparing meals; after using the restroom, changing a babies diaper, or assisting a child or infirm person on the toilet; and after touching animals, or handling animal waste.
• Try to avoid ingesting water that may potentially be contaminated. Don't swallow water when swimming in public swimming pools. Don't drink untreated water from rivers, streams or lakes, no matter how pure it may look, as microbial cysts may be washed into theses systems from the faeces of infected animals. Always take precautionary measures when travelling, particularly in undeveloped regions – boil water, filter water, or buy bottled water to be on the safe side.
• Home drinking water filters are recommended to filter out tap water that may be contaminated with Cryptosporidium and/or Giardia. When choosing a filter look for one that will purify the water of these bacteria like the Berkey does.

Airway Heights city officials issues an advisory warning residents not to use tap water for drinking or cooking as chemical contaminants originating from Fairchild Air Force Base have been found in the city's drinking water wells. However, according to a joint statement released by the Air Force and city officials, the water "is safe for activities where water will not be ingested, such as bathing, doing laundry and washing dishes," stressing that the advisory was issued "out of an abundance of caution."

Residents have been supplied with packs of bottled water to meet their drinking and cooking requirements while the affected drinking water wells are flushed — which could take as long as ten days.

Industrial chemical contaminants known as perfluorinated chemicals (or more commonly as PFOS or PFOA), which were identified as hazardous contaminants by the EPA las year, were initially found in several private wells on the eastern side of Fairchild. The chemicals are thought to have originated from firefighting foam used on the Air Force base from 1970 through to last year for fire training exercises, and at two aircraft crash sites.

Fairchild city officials initially began testing groundwater samples collected from the base in February this year, and followed up by testing water samples outside the base at the beginning of April. They recently expanded their search for these contaminants to include areas further to the east and south of the Air Force Base, and found concerning levels of PFOS/PFOA contaminants in water from 17 or more wells. Out of four wells supplying Airway Heights' residents with drinking water, three were found to be contaminated.

According to Airway Heights mayor, Kevin Ritchey, the city will cease pumping water from the contaminated wells and link up with the water system supplying the city of Spokane, which is typically utilized during summer to help meet the extra demand for water during this period. The city has begun flushing affected wells to reduce the concentrations of the PFOS/PFOA chemicals to safer levels, and while this should take affect within 3-4 days, test results to confirm this will only be available later.

"The problem is the test results take about a week, so we're talking seven to 10 days to be completely sure" the contamination is reduced, Ritchey said.

According to the EPA, most of us have low levels of PFOS chemicals in our bodies due to exposure to these chemicals in everyday consumer products. However, scientific research has shown that high concentrations of these chemicals are associated with adverse health issues in animals.

"We care about the health and well-being of our families, neighbors and community partners, and we understand those impacted, or potentially impacted, by this emerging issue have legitimate concerns," Air Force Col. Ryan Samuelson said in the statement.

Officials are currently assessing alternative options for the city's water supply and are also considering installing water filtration systems onto wells affected by contamination. If you are affected by this or other water quality issues, you can be proactive and take measures to ensure your water is free from contaminants and safe to drink by investing in a good quality drinking water filter like a Berkey that is capable of removing harmful chemicals and other hazardous contaminants.

The average American tends to take safe drinking water for granted; that is until a new drinking, water crisis such as the Flint lead contamination saga, surfaces, leading everyone to wonder what contaminants might be lurking in the water that flows from their taps.

The Flint water crisis was certainly a wake-up call for American consumers, and according to Erik Olson, director of the Natural Resource Defense Council's Health program, when it comes to water safety issues, Flint is not an isolated case. Millions of Americans living in other towns and cities around the country are supplied with water contaminated with lead or other pollutants.

The NRDC together with the NGO Clean Water Action have been hard at work trying to enforce the federal Safe Drinking Water Act, serving as a public watchdog during every stage of the process. While these organizations have realized many victories in their fight for clean water, consumers should still be cautious about potential pollutants that may be present in their water supply or distribution network.

Lead is Not the Only Issue

All water suppliers providing drinking water to consumers in the US must ensure that the water they supply meets drinking water safety standards. If these standards are met, consumers can safely drink the water that flows from their taps. However, violations are widespread, and very often water supplied to consumers contains pollutants that are not regulated by the EPA.

A recent NRDC report shows that in 2015, around 77 million US consumers received drinking water from water systems that were in violation of federal protections, and more than 30% of these consumers were dependent on water supplies that failed to meet federal health standards. Furthermore, water suppliers serving millions of other US consumers either didn't conduct adequate water safety tests or failed to warn consumers or report the results of these tests to the health authorities. Considering that many pollutants are not even regulated or monitored, these figures are likely to be an understatement rather than a true reflection of how widespread the problem is. For example, pollutants such as PFOA/PFOS and perchlorate occur in tap water across America, but they are not regulated and therefore are not included in the already staggeringly high figures mentioned above.

Children, pregnant women and people with compromised immune systems face a higher health risk when exposed to the following pollutants:

• Lead - a heavy metal that can leach into water from lead water pipes, fixtures and fittings, particularly when corrosive water is moving through the system, can cause behavioral and neurological problems in children and also pose a health risk to adults.

"It's a more common problem in cities with older water systems," explains Kristi Pullen Fedinick a scientist with NRDC Health program, "but what a lot of people don't realize is that even relatively new brass fixtures and faucets can still contain significant amounts of lead. Just because your home is less than 20 years old doesn't necessarily mean you're lead-free."

• Atrazine - an endocrine-disrupting pesticide that is widespread in US freshwaters, as well as drinking water supplied to homes across the Midwest and southern states.

• Pathogens - disease causing parasites, bacteria and viruses can make their way into drinking water supplies that are not properly treated to kill these pathogens.

• Chlorine treatment by-products - when present in high concentrations, by-products of the water disinfection process may pose a health risk, including a risk of cancer and a reproductive health risk.

• Other contaminants - arsenic, nitrates, radioactive contaminants, vinyl chloride, perchlorate and pharmaceuticals are other potentially hazardous contaminants found in drinking water across the country.

To ensure that you water is free from these contaminants we highly recommend that you filter your drinking water with a good quality drinking water filter from our range of Berkey filters.